module Digest::Instance

contains no line feeds.
In either case, the return value is properly padded with '=' and

initial state before and after the process.
+string+ in a base64 encoded form, resetting the digest to the
If a +string+ is given, returns the hash value for the given

in a base64 encoded form, keeping the digest's state.
If none is given, returns the resulting hash value of the digest

def base64digest(str = nil)
  [str ? digest(str) : digest].pack('m0')
end